Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!

Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.

I have designed a ram air intake for my turbo setup with a metal screen cartridge. this intake goes from where one of the headlights used to be to the turbo.
I am concerned if this is not such good idea since at high speed you will be creating a posative pressure (maybe) on the inlet side of the turbo.
The benefit is a nice cold air charge to the turbo which here in St lucia is very desirable.
Since the picture below was taken I have smoothed out the intake pipe before the turbo.
Has anyone done this before and can give some input?

i personally would create some sort of a screen on it to keep the turbo from eating anything it should not but it looks nice! You could use ( the tech word is escaping me now) a bell shaped piece which would help with the positive pressure issue.

I saw a setup similar to this on a 1000HP Supra not too long ago. They used a screen to keep out major debris. I think it is a great idea. Your boost controller should negate any fluctuations due to positive pressure on the suction side of the turbo. Obviously I don't think this is a good setup for a street car. I might consider having two headlights and a filter for a street car.

i personally would create some sort of a screen on it to keep the turbo from eating anything it should not but it looks nice! You could use ( the tech word is escaping me now) a bell shaped piece which would help with the positive pressure issue.

Velocity stack maybe or anti surge turbo housing.

I seem to remember a friend doing an experiment a long time ago using the stock GC8 scoop to see if he could make boost using a ram air setup. I don't remember exactly what happened but it didn't even equalize pressure to 0 much less make positive pressure.

If this is an all out drag car which will only be used on the track (looks like it is) the screen should do. If you plan on driving it to car shows or on the street frequently you should definitely find a way to stick a filter in there.

I am concerned if this is not such good idea since at high speed you will be creating a posative pressure (maybe) on the inlet side of the turbo.

Yes, at speed you will be creating a small positive pressure at the compressor inlet.
Why would you think that that would be a bad thing?

Since pressure recovery for ram boost is never perfect you might get 60%-70% of theoretical ram boost.

At 100 mph 100% recovery would be about 0.17 psi ram, so you will see about 0.12 psi ram as you trap.
This is compared to the -0.5 psi to -1 psi you would see on a conventional intake with air filter. On a drag only car it is a good mod.

I dont have a current pic since the car in a container on another Island waiting for a drag event.
But it is fabricated from 4" pipe with a tubular cartridge containing 3 metal screens. course, med and fine. the screens are backed by several cross braces to eliminate a colapse into the turbo in case of a large foreign object injestion (sp?).
Since that picture the intake pipe to the turbo has been smoothed considerably.
intake temps have dropped between 10-20 deg F from before so I think it is worthwhile . It required a fairly substantial increase in fueling to maintain A/F at top end from the old airfiter intake so there should be some extra horses there now.
I was just worried I might damage the turbo long term.